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Map showing publication footprint
  • Usage in publication:
    • Black Rock diabase*
  • Modifications:
    • Original reference
  • Dominant lithology:
    • Diabase
  • AAPG geologic province:
    • New England province
    • Hartford basin
Publication:

Emerson, B.K., 1898, Holyoke folio, Massachusetts-Connecticut: U.S. Geological Survey Geologic Atlas of the United States Folio, GF-50, 8 p., scale 1:125,000


Summary:

Also USGS Monograph 29, p. 17-18, pl. 34. Black Rock diabase. Volcanic plugs parallel with Holyoke Range and 1 mile southeast of it, intrusive into Triassic and Jurassic sediments [Newark group]. One is quartz diabase; others are similar to bedded trap rock but are fresher and form domes. Age is Triassic-Jurassic. Present in Mount Holyoke region.
Named from outcrops at Black Rock, south of Mount Holyoke House, Mount Holyoke quadrangle, Hampshire Co., central MA.

Source: GNU records (USGS DDS-6; Reston GNULEX); supplemental information from US geologic names lexicon (USGS Bull. 896, p. 206).


Map showing publication footprint
  • Usage in publication:
    • Black Rock diabase†
  • Modifications:
    • Abandoned
  • AAPG geologic province:
    • New England province
    • Hartford basin
Publication:

Emerson, B.K., 1917, Geology of Massachusetts and Rhode Island: U.S. Geological Survey Bulletin, 597, 289 p.


Summary:

Pg. 272. Black Rock diabase is not an isolated intrusive plug as first supposed, but is a part of the Hampden diabase flow, of Newark group, which is interbedded in Longmeadow sandstone.

Source: US geologic names lexicon (USGS Bull. 896, p. 206); GNU records (USGS DDS-6; Reston GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Black Rock diabase breccia dike
  • Modifications:
    • Overview
    • Revised
  • AAPG geologic province:
    • New England province
    • Hartford basin
Publication:

Balk, Robert, 1957, Geology of [the] Mount Holyoke quadrangle, Massachusetts: Geological Society of America Bulletin, v. 68, no. 4, p. 481-504.


Summary:

Black Rock diabase breccia dike in Granby tuff consists of fragments of diabase, tuff, and sedimentary rocks in diabase matrix. Cuts basal sediments above Holyoke diabase sheet.

Source: GNU records (USGS DDS-6; Reston GNULEX).


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For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

Asterisk (*) indicates published by U.S. Geological Survey authors.

"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).

Slash (/) indicates name conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).

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